A male “shell parakeet,” or budgerigar, is far more likely to be tempted into an illicit affair when out of sight of his vengeful mate, biologists Aliza Baltz and Anne Clark of the State University of New York at Binghamton reported in the journal Animal Behavior.
The small green parrots usually live in stable pairs when raising their young. During the breeding season, males bring home the food while females guard the nest.
The scientists studied 13 pairs of budgies as they were starting to breed, exposing each male to a new female twice--once under the stern stare of his mate and once while she was hidden behind a screen. Almost three-quarters of the male birds’ distinctive courting behavior occurred when their mates could not see them.